//You are given two non-empty linked lists representing two non-negative 
//integers. The digits are stored in reverse order, and each of their nodes contains a 
//single digit. Add the two numbers and return the sum as a linked list. 
//
// You may assume the two numbers do not contain any leading zero, except the 
//number 0 itself. 
//
// 
// Example 1: 
//
// 
//Input: l1 = [2,4,3], l2 = [5,6,4]
//Output: [7,0,8]
//Explanation: 342 + 465 = 807.
// 
//
// Example 2: 
//
// 
//Input: l1 = [0], l2 = [0]
//Output: [0]
// 
//
// Example 3: 
//
// 
//Input: l1 = [9,9,9,9,9,9,9], l2 = [9,9,9,9]
//Output: [8,9,9,9,0,0,0,1]
// 
//
// 
// Constraints: 
//
// 
// The number of nodes in each linked list is in the range [1, 100]. 
// 0 <= Node.val <= 9 
// It is guaranteed that the list represents a number that does not have 
//leading zeros. 
// 
// Related Topics Linked List Math Recursion 👍 14805 👎 3245

  
package leetcode.editor.en;

import listnode.ListNode;

public class _2_AddTwoNumbers{
    public static void main(String[] args) {
         Solution solution = new _2_AddTwoNumbers().new Solution();
    }
    //leetcode submit region begin(Prohibit modification and deletion)
/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode() {}
 *     ListNode(int val) { this.val = val; }
 *     ListNode(int val, ListNode next) { this.val = val; this.next = next; }
 * }
 */
class Solution {
    public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
        ListNode pre = new ListNode();
        ListNode cur = pre;
        int i = 0;
        while (l1!=null || l2!=null){
            int i1 = l1 == null ? 0 : l1.val;
            int i2 = l2 == null ? 0 : l2.val;
            int sum = i1 + i2 + i;

            i = sum>9?1:0;
            sum%=10;
            cur.next = new ListNode(sum);
            cur = cur.next;
            l1 = l1 != null?l1.next:null;
            l2 = l2 != null?l2.next:null;
        }
        if (i ==1){
            cur.next = new ListNode(i);
        }
        return pre.next;
    }
}
//leetcode submit region end(Prohibit modification and deletion)

}